IssueTracker

You have to jump through hoops to both:
* Set sharedPreferences
* Watch for changes in sharedPreferences

for simple things like persistent UI state (beyond remembered state).

In my implementations, I'm duplicating state between the viewmodel and the preferences (loading prefs on instantiation), and updating them both with a "setValue" on the viewmodel.

Putting all the boilerplate into the viewmodel for a bunch of observable UI states based on preferences is overly verbose, and the preferences might be 1:1 with the viewModel anyway.

There should be an out-of-the-box mechanism for quickly setting a shared preference and observing the results to cause a recomposition.

Example usecase: Conditionally showing an AlertDialog based on the current app version, compared to a last seen app version.

val currentVersion = stringResource(R.string.current_app_version)
val lastSeen = ObservableSharedPreference("lastSeenVersion","") // default shared preferences
if (lastSeen.value < currentVersion){
  AlertDialog(
    text={Text(currentVersion)},
     onDismissRequest = {
          lastSeen.value = currentVersion // or
          lastSeen.apply(currentVersion) // or
          lastSeen.commit(currentVersion) // with setValue being whatever makes sense for the recomposition usecase, either commit or apply
    }
  )
}

I was going to provide an example of putting the business logic on a viewmodel and updating an ObservableSharedPreference from there (e.g. calling "viewModel.setHasSeenLatestVersionReleaseNotes()" from onDismissRequest), but the amount of boilerplate required doesn't justify not treating the sharedPreferences as the model+viewmodel. Other example usecases might be DarkModeOverride, CurrentActiveViewEnum, EditModeEnabled, EnabledColumnsBitMask etc. Some may justify transforms in business logic, but most of these don't, IMO.

Either way,

class MyViewModel : ViewModel() {
  var viewMode by observableDefaultSharedPreferenceOf("viewMode","")
  var lightMode by observableDefaultSharedPreferenceOf("lightMode",true)
  // nothing else
}

looks reasonably approachable.